This invention relates to stacked fuel cell structures with cell support elements and electrical interconnectors and particularly to such support elements and interconnectors for air-depolarized cells which require electrode material and electrolyte maintenance.
Fuel cells of individual cells, particularly of flat plate configuration, are often arranged in blocks or stack structures of electrically interconnected cells, into batteries of desired power. In the past, various means have been used for holding the cells in position relative to each other and for electrically interconnecting the cells. Often these means are unrelated and accordingly there is a substantial volumetric loss, excessive complication of elements and overall weight, as well as difficulty in removing and servicing the individual cells. In addition, both fuel cell battery holding structures are of an enclosure type and the electrical connective elements tend to render enclosed cells difficult to access, replace, or service. For fuel cells, ease of service is of particular importance because of the need for replacing depleted materials, particularly electrolyte in air-depolarized cells, as well as anode material exchange to facilitate quick zinc fuel exchanging (i.e., xe2x80x9cmechanical rechargingxe2x80x9d) in air depolarized cells.
It is accordingly an object of the present invention to provide a structure for fuel cells for construction into a modular battery structure with integrated fuel cell stacking and support means and electrical interconnection means.
It is a further object of the present invention to provide such battery structure which permits quick removal and interconnection of fuel cell elements for service and replacement (in particular, mechanical recharging of anode materials).
It is yet another object of the present invention to provide a battery structure which includes means for air circulation for use with air depolarized fuel cells.
Generally the present invention comprises a fuel cell battery structure comprising at least two fuel cells and an electrical connector block. The fuel cells are electrically interconnected into a battery structure via the connector block. Each fuel cell comprises an anode and cathode element and each of the anode and cathode elements of each cell are provided with a terminal conductor element externally positioned on one side of the respective fuel cells. The connector block comprises a series of conductive elements adapted for electrical and mechanical engagement with the respective terminal conductor elements of the anode and cathode elements of each of the fuel cells on said one side of the respective fuel cells. The connector block further comprises means for electrically connecting the anodes and cathodes of the stacked cells into a desired electrical interconnection. In addition, the block mechanically holds the respective fuel cells on one side of the block, in a fixed position as a result of the mechanical engagement. As a result, another side of each of the fuel cells remains exposed to permit disengagement and removal of the fuel cells from the block.
Generally the present invention comprises means for forming a stack of fuel cells into a unique overall fuel cell (in particular air depolarized cells such as zinc/air cells) or battery structure, wherein a single structural element provides means for cell support and stacking and electrical interconnection of the cells into a desired electrical configuration. In addition, the structural element is preferably configured with air duct means to facilitate air circulation to the individual cells, with concomitant increase in discharge rate capability.
In accordance with the present invention, flat plate fuel cells and batteries of cells, particularly air-depolarized cells, are stacked and electrically interconnected into a battery structure with a connector block and optional support tray. The anode and cathode elements of each cell are provided with extending terminal conductor elements, preferably extending in downward xe2x80x9cUxe2x80x9d shaped configuration from the upper ends of the anode and cathode elements respectively, to provide maximum physical support. However, other extension configurations (e.g., upwardly extending, laterally extending, etc., as well as reversal of the male and female elements) are similarly operable and are included in the present invention.
In a preferred embodiment the connector block comprises a series of conductive apertures, positioned and sized to accommodate the terminal conductor elements of the electrodes therein. The connector block further comprises electrical interconnecting elements to electrically connect the electrodes of the stacked cells in a desired electrical interconnection (serial, parallel and mixed serial and parallel segments). Available, electrically mating male and female plug connections such as banana plugs are preferably used in conjunction with the electrode collectors of the cells and imbedded in the block, to effect both the electrical interconnection and mechanical support between the cells and the connector block. The interconnection between terminal conductor elements and the respective apertures further serves to support and orient the cells in a minimal volume and permits selective rapid cell removal for replacement or servicing and xe2x80x9cmechanical rechargingxe2x80x9d. The cells are also preferably provided with keyed members for keyed interlocking with a support tray having co-fitting keying elements to provide full structural integrity for the stacked cells. Lateral end elements extend between the connector block and support tray to complete an open enclosure and provide a support base for air circulating devices, such as fans, in an xe2x80x9cair management systemxe2x80x9d and also support the block in a suspended position suitable for engagement with the individual fuel cells.